Take Control Of Cars Wirelessly

The researchers were able to control everything from the car's brakes to its door locks to its computerized dashboard displays by accessing the onboard computer through GM's OnStar and Ford's Sync, as well as through the Bluetooth connections intended for making hands-free phone calls...

...the researchers systematically analyzed ways they could get at a car's computer systems without having physical access. They used a 2009 mass-production sedan equipped with fewer computer systems than many high-end cars. For each attack that succeeded, they confirmed that they could take complete control of all of the car's internal computer systems...

The researchers attacked the car's Bluetooth system, which allows a driver to make hands-free cell-phone calls. They found a vulnerability in the way the Bluetooth system was implemented that allowed them to execute code to take control of the car.

The researchers were also able to hack into cars by using cellular connections that work automatically, like calling for help if the car is damaged.

"We were surprised to find that the attack surface was so broad," Kohno says, referring to the wide variety of ways the researchers were able to gain access to the car's computer systems.

SF writer Keith Laumer had the same idea in his 1965 novel A Plague of Demons:

I nudged the car into motion, steering between the two wide-shouldered, lean-hipped trouble boys. One whipped out a three-inch black disc - a police control-override. A red light blinked on the dash; the car faltered as the external command came to brake.
(Read more about Laumer's police control-override)

Modern day sf readers also recall with delight the Cop Block from Greg Bear's excellent 2007 novel Quantico:

All cars and trucks in the U.S. were now required to have Cop Block. A patrol car could radio a coded signal that slowed and then shut down the engine. Workarounds were illegal and the fines were expensive, plus real jail time...